This chapter provides a critical review of studies searching for ways to improve teacher and school effectiveness in an attempt to compare the effect of different improvement approaches including the Dynamic Approach (DA). Specifically, the first two parts of this chapter refer to studies investigating the impact on student learning outcomes of using the DA to establish teacher and school improvement programmes respectively. The methods and findings of these experimental studies are presented and their strengths and limitations are discussed. We also investigate the sustainability of using the DA for teacher and school improvement purposes and the feasibility of testing the main assumptions upon which the DA is based. In this way not only is the added value of using the DA to promote quality and equity at classroom and/or school level examined, but its indirect effects on student learning outcomes through improving teacher and school factors are also investigated. In the final section of this chapter, a synthesis of improvement studies conducted during the last 12 years (i.e., from 2005 until 2017) is presented. The main findings of this synthesis help us identify links between the DA to teacher and school improvement, and other teacher and whole-school improvement approaches used in different contexts. Implications for research on teacher and school improvement are also drawn.